The ureters are long, narrow tubes that carry urine from the kidneys to the urinary bladder. They are a vital part of the urinary system and play a crucial role in the excretion of waste products from the body.
The ureters are approximately 25-30 cm in length and are composed of three layers: the inner mucosa, the middle muscular layer, and the outer fibrous coat. The muscular layer consists of smooth muscle that contracts in a peristaltic fashion to propel urine towards the bladder.
The primary function of the ureters is to transport urine from the kidneys to the urinary bladder. Peristaltic contractions of the smooth muscle in the ureter walls help to propel urine downwards, even against gravity, to ensure a unidirectional flow of urine.